Application of microbially induced calcite precipitation to prevent soil loss by rainfall: effect of particle size and organic matter content

• Published in: Journal of soils and sediments Vol. 21; no. 8; pp. 2744 - 2754
• Main Authors: Chung, Hyeonyong, Kim, Sang Hyun, Nam, Kyoungphile
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2021; Springer Nature B.V
• Subjects: Atmospheric precipitations; Calcite; Calcium; Calcium carbonate; Calcium ions; Chemical precipitation; Civil engineering; Clean Up Korea 2019; Earth and Environmental Science; Environment; Environmental engineering; Environmental Physics; Loam; Organic matter; Particle size; Precipitates; Precipitation; Rain; rain intensity; Rainfall; Rainfall intensity; Reduction; Sand; Sandy loam; sandy loam soils; Soil; Soil analysis; Soil erosion; Soil Science & Conservation; Soil strength; Soils; Sporosarcina pasteurii; Strength; Urea; Microbially induced calcite precipitation; Soil loss by rainfall; Penetration resistance; Rainfall intensity
• ISSN: 1439-0108; 1614-7480
• DOI: 10.1007/s11368-020-02757-2

Purpose Soil loss by rainfall is a serious problem in civil and environmental engineering. In this study, microbially induced calcite precipitation (MICP) was applied to reduce rainfall-induced soil loss. Furthermore, the effects of particle size and organic matter content were investigated. Materials and methods A mixture of Sporosarcina pasteurii , 450 mM urea, and 450 mM calcium ions was introduced to sand and sandy loam with 2.6% organic matter content to induce MICP. Artificial rainfall and penetrometer tests were conducted to analyze the soil loss and surface strength, respectively, of the MICP-applied soils. Results As MICP was applied, the concentration of CaCO 3 precipitates increased linearly (9.8 mg CaCO 3 /g-soil/application), but the strength of the soil reached a plateau of 23.9 ± 1.2 N/mm after five repeated applications (54.5 ± 3.6 mg CaCO 3 /g-soil). Only after two repeated MICP applications, up to 84% of reduction in loss rate was accomplished in sand under the worst conditions (rainfall intensity of 75 mm/h, slope of 15°), while only 58% of reduction was obtained after five repeated applications in sandy loam with 2.6% organic matter. For the same amount of CaCO 3 precipitates, the strength was higher in sand with larger particle size. Lower organic matter content led to the higher strength. SEM revealed that larger CaCO 3 precipitates were obtained in sand with lower organic matter content. Conclusion Our results indicate that the effect of MICP on the prevention of rainfall-induced soil loss is promoted when the particle size is larger and organic matter content is lower.